### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java,v
retrieving revision 1.14
diff -u -r1.14 InternalCompletionProposal.java
--- codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java	22 Jan 2009 09:46:59 -0000	1.14
+++ codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java	25 Jun 2010 09:45:11 -0000
@@ -311,7 +311,25 @@
 			for(int i = 0;	i< length ; i++){
 				args[i] = new String(paramTypeNames[i]);
 			}
-			IMethod method = type.getMethod(new String(selector),args);
+			// https://bugs.eclipse.org/bugs/show_bug.cgi?id=316937
+			// BinaryType#getMethod() creates a new instance of BinaryMethod, which is a dummy.
+			// Instead use IType#findMethods() to get a handle to the method.
+			IMethod method = null;
+			{
+				IType enclosingType = type.getDeclaringType();
+				if (enclosingType != null && CharOperation.equals(type.getElementName().toCharArray(), selector)) {
+					String[] newArgs = new String[length + 1];
+					newArgs[0] = Signature.createTypeSignature(enclosingType.getFullyQualifiedName(), true);
+					System.arraycopy(args, 0, newArgs, 1, length);
+					method = type.getMethod(new String(selector), newArgs);
+				} else {
+					method = type.getMethod(new String(selector), args);
+				}
+				IMethod[] methods = type.findMethods(method);
+				if (methods != null && methods.length > 0) {
+					method = methods[0];
+				}
+			}
 			try{
 				parameters = new char[length][];
 				String[] params = method.getParameterNames();
Index: model/org/eclipse/jdt/internal/core/BinaryMethod.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/BinaryMethod.java,v
retrieving revision 1.105
diff -u -r1.105 BinaryMethod.java
--- model/org/eclipse/jdt/internal/core/BinaryMethod.java	7 Mar 2009 00:58:57 -0000	1.105
+++ model/org/eclipse/jdt/internal/core/BinaryMethod.java	25 Jun 2010 09:45:12 -0000
@@ -181,7 +181,10 @@
 
 	// try to see if we can retrieve the names from the attached javadoc
 	IBinaryMethod info = (IBinaryMethod) getElementInfo();
-	final int paramCount = Signature.getParameterCount(new String(info.getMethodDescriptor()));
+	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=316937
+	// Use Signature#getParameterCount() only if the argument names are not already available.
+	final int paramCount = info.getArgumentNames() == null ? info.getArgumentNames().length : 
+										Signature.getParameterCount(new String(info.getMethodDescriptor()));
 	if (paramCount != 0) {
 		// don't try to look for javadoc for synthetic methods
 		int modifiers = getFlags();